Transmitting of data from a content provider to subscribers in a protected format, such as radio and television programs transmitted in encrypted or scrambled form from a television or radio station via cable or satellite, is in widespread use today. Generally, the protected data has to be decoded at the receiving station, such as a cable or satellite set-top-box, prior to its display or playback to a user. One form of such decoding is performed via the insertion of a cable or satellite card into an open slot of the set-top-box. The inserted card includes one or more access keys which can be used to decode the protected data so that its content can be retrieved for viewing or listening.
A growing problem in the foregoing approach is an increasing number of proposed and legacy audio-video (AV) encoding standards. This increasing number of AV encoding standards will likely create compatibility problems for a given set-top-box, which needs to accommodate AV encoding of programs transmitted by the content provider and AV decoding of such programs for display by a viewer's television. For example, the content provider may use an encoding standard of Motion Picture Expert Group 4 (MPEG 4), while the set-top box is adapted to decompress content formatted in accordance with an MPEG 2 standard.
Currently, an externally inserted cable or satellite card would be used to perform both the decoding of the received program and the transcoding of the received program from one encoding standard to another, such as from MPEG 4 to MPEG 2. Due to the relative expense of providing the viewers with externally inserted cable and satellite cards, however, makers of set-top-box are in the process of incorporating the card's functionality into the set-top-box. While this approach may prove effective for the decoding functionality of the cable and satellite cards, it greatly reduces the programmability of a set-top box in accommodating different encoding standards through transcoding operations, so to be compatible with both formats of content delivered by the content provider and processed by the viewer's display device.
Accordingly, there will be a need for providing set-top-boxes which do not use traditional external cards for decoding a received program, but with the ability to transcode received programs into formats compatible with the display device on which the program is to be shown.